First, an elastomer, most often nitrile, is vulcanised to a metal ring. This creates a stiffening effect that includes a specialised metal tension spring directly behind the sealing lip, keeping the oil seal firmly in place against the moving part.
Special seal types and their features
Table 4: JTEKT oil seal type codes and corresponding ISO and JIS standards
Oil seals go by many names, such as shaft seals, dirt seals, grease seals, lip seals, and many other variations of these. They are essentially simple devices used in rotary shaft equipment to prevent lubricant from escaping and for excluding contaminants such as dust, dirt and water. An oil seal’s most important function, however, is that it protects every type of ball, sleeve and roller bearing in the rotating shafts. The seals also prevent the integration of two different fluids that shouldn’t mix, such as oil and water.
2. Chemical resistance High temperature rubber gaskets are resistant to a wide range of chemicals, including acids, bases, and solvents. This property makes them suitable for use in chemical processing industries.Figure 2.9. Metal to rubber bonded seal
Geographically, Asia Pacific is expected to dominate the oil seal market during the forecast period, followed by Europe and North America
Polytetrafluoroethylene
Chemical resistant
Low coefficient of friction poor elastic properties not wear resistant if used by dynamic applications